1. Field of the Invention
The present invention relates to a sewing machine, and more particularly to a drive structure for driving an upper thread wiper of a sewing machine.
2. Description of the Prior Art
Conventionally, the power source of a drive structure for an upper thread wiper of a sewing machine is transmitted by a mainshaft which is mounted on a base of the sewing machine, which a continuous power transmitting system. The structure of this kind of power transmitting system is complicated and difficult to adjust, and consequently has a high manufacturing and maintenance cost. Hence, the applicant of this application has invented “a coaxially clockwise driven needle shaft and upper thread wiper of a sewing machine”, wherein the structures of the power of the upper thread wiper and the needle shaft have been simplified. However, the applicant of the present invention is not satisfied with the improvement made in the “a coaxially clockwise driven needle shaft and upper thread wiper of a sewing machine” and has made further improvement to the drive structure for the upper thread wiper.